Hip orthosis, method for preventing the dislocation of a hip and use of a hip orthosis

ABSTRACT

A hip orthosis, provided with a trunk engaging part and an upper leg engaging part which are intercoupled by coupling means, wherein the coupling comprise at least one resilient element for operatively preventing an adducting movement of an upper leg engaged by the upper leg engaging part by means of spring force.

The invention relates to a hip orthosis, provided with a trunk engagingpart and an upper leg engaging part which are intercoupled by couplingmeans.

The invention further relates to a method for preventing the dislocationof a hip.

The invention further relates to the use of a hip orthosis according tothe invention, for preventing the dislocation of a hip, for instanceduring recovery from hip surgery.

Many forms of surgery of a hip joint or an upper part of the thighrequire an incision in the muscles and/or tendons near the hip joint ofa patient. These muscles and tendons provide the movement of the hip,but also ensure that the hip ball is kept in its socket. During therecovery from hip surgery, the muscles and tendons will be weakened andwill, in many cases, not be able to keep the hip ball in its socket.After hip surgery, there is therefore an increased risk of a hip comingout of its socket (hip dislocation). In addition to causing severe pain,such a hip dislocation may make it necessary for the patient to havesurgery again in order to place the hip ball in its socket.

A hip orthosis for preventing the dislocation of a hip is known fromAmerican patent publication. U.S. Pat. No. 6,540,703. The known hiporthosis is provided with an adjustable hinge which, in use, only allowsrotation of the upper leg about the hip joint in forward and backwarddirection. This binge enables a person wearing a hip orthosis to movethe upper leg with respect to the trunk about an axis of rotation of thehinge, so that the person can make a more or less normal walkingmovement. Here, the freedom of movement can be limited in an adjustablemanner. The upper leg recedes outwards with respect to the trunk at apredetermined fixed angle for preventing the dislocation of the hipafter, for instance, placement of a hip prosthesis.

The known hip orthosis has the drawback that, if the person is sittingor is going to sit, the trunk engaging part, which is arranged forengaging the trunk of the person in use, and the upper leg engagingpart, which is arranged for engaging the upper leg of the person in use,can exert such forces on each other that the orthosis tends to twistaround the trunk, so that correct positioning of the upper leg withrespect to the trunk is not guaranteed. In addition, in order to preventtwisting, the known hip orthosis needs to be laced up very tightlyaround the trunk, which adversely affects the wearing comfort. Inpractice, this is often solved by a wearer of the orthosis by making thelacing looser, which cancels the effect of the orthosis.

It is an object of the invention to provide a hip orthosis which keepsthe upper leg positioned correctly with respect to the trunk during use,while the orthosis has a great wearing comfort.

To this end, the invention provides a hip orthosis which ischaracterized in that the coupling means comprise at least one resilientelement for operatively preventing an adducting movement of an upper legengaged by the upper leg engaging part by means of spring force. Due tothe resilient element, the orthosis is able to, operatively, exert aforce and/or a moment on the upper leg which makes the upper leg abduct,viewed from the front side of the person, preferably independently ofthe position of the upper leg with respect to the trunk. In addition,the person has more freedom of movement, since the upper leg can thuspreferably move in all directions and not only in one direction whichis, for instance, determined by a hinge, while a desired interplay offorces can continue to act on the hip. This offers more comfort and, inaddition, the possibility of m ore efficient exercise of the musclesaround the hip joint, which muscles are weakened due to, for instance,surgery, in which a hip prosthesis has been placed. It is noted that theterm ‘adduction’ can be defined as being a movement towards the trunk.The term ‘abduction’ can be defined as being a movement by which a bodypart is moved away from the axis of the body.

Preferably, in use, the at least one resilient element exerts a force onthe hip joint, such that the hip is pressed into its socket under theinfluence of that force, so that the risk of dislocation is reducedfurther.

Preferably, in use, the at least one resilient element exerts a momention the hip joint. This allows the upper leg to be given a preferredposition with respect to the trunk and/or to rotate it to a preferredposition.

More preferably, in use, the moment is directed such that, under theinfluence of the moment, the upper leg is rotated substantiallyoutwards, at least into a direction transverse to the sagittal plane.Thus, too great an abduction of the upper leg (towards the other leg),which increases the risk of dislocation of the hip, can be prevented.

Preferably, the coupling means comprise a connecting part connected withthe upper leg engaging part and a coupling part connected with the trunkengaging part, while, during use, this connecting part is rotatableabout a point of rotation with respect to this coupling part. This pointof rotation is, for instance, a virtual point of rotation. Preferably,the orthosis, in particular the trunk engaging part, is designed suchthat, in use, the point of rotation is located on a line whichintersects the two hip balls of a wearer of the orthosis. This offersthe advantage that the freedom of movement of the upper leg issubstantially not hindered with regard to a rotation about the hip ball.

Preferably, in use, the connecting part and the coupling part arepretensioned with respect to each other. This offers the advantage thatthe upper leg engaging part and the trunk engaging part can exert aforce and/or moment on the hip joint in a simple manner.

Preferably, the connecting part comprises the resilient element, inparticular a leaf spring, so that the orthosis can have a relativelyinexpensive, compact and light design.

Preferably, it holds that, if the upper leg engaging part has beenfitted to the upper leg, the leaf spring recedes away from the upper legin unloaded condition and is tensioned along the upper leg in loadedcondition.

This offers the advantage that, if the trunk engaging part has beenfitted to the trunk in a simple manner, a force and optionally a momentcan be applied around the hip joint.

Preferably, in use, the connecting part and the coupling part engageeach other at least in a point of contact, which operatively moves withrespect to the trunk engaging part if the upper leg is moved relative tothe trunk. Preferably, in use, the point of contact is located at adistance from the point of rotation. Thus, in a simple manner, a momentcan be applied around the hip joint. Varying the point of engagementoffers the advantage that the direction of the moment on the hip jointcan vary with respect to the trunk if the upper leg is moved relative tothe trunk.

Preferably, in use, the connecting part reaches beyond the point ofrotation, viewed in a direction from the upper leg engaging part towardsthe point of rotation. Preferably, the coupling part at least engagesthe portion of the connecting part reaching beyond the point ofrotation, with different rotational positions of the connecting part.The advantage of this is that, at all times, irrespective of whether theperson is walking, standing, sitting or lying, a moment can be exertedon the hip joint, which moment is directed such that the knee is pressedsubstantially outwards, at least in a direction transverse to thesagittal plane. Thus, too great an adduction of the upper leg, whichincreases the risk of dislocation of the hip, can be prevented.

Preferably, the connecting part is slidably coupled to the couplingpart. Thus, the movement of the point of contact during the movement ofthe upper leg engaging part with respect to the trunk engaging part canbe realized in a simple and inexpensive manner. In addition, thus, theupper leg engaging part substantially does not exert any force on thetrunk engaging part in tangential or axial direction. This reduces thetendency of the trunk engaging part to twist around the trunk.

In one embodiment, the connecting part comprises a rod-shaped end andthe coupling part is arranged for operatively preventing an outwardmovement of the rod-shaped end with respect to the trunk engaging part.

Thus, in a simple and inexpensive manner, a force and a moment can beapplied to the hip joint.

In another embodiment, the connecting part comprises an annular end andthe coupling part is arranged for operatively preventing an outwardmovement of the annular end with respect to the trunk engaging part.Thus, likewise, in a simple and expensive manner, a force and a momentcan be applied to the hip joint.

The method according to the invention is characterized in that an inwardmovement of the associated upper leg is prevented by means of springforce. Preferably, the force is substantially directed such that the hipis pressed into its socket under the influence of that force. Thisfurther reduces the risk of dislocation. Preferably, the upper leg isrotated substantially outwards, in a direction transverse to thesagittal plane, by a moment. Thus, too great an adduction of the upperleg (towards the other leg), which increases the risk of dislocation ofthe hip, can be prevented. By these measures, movement of the upper legin forward, backward and sideward direction is preferably not prevented.This offers more comfort and the possibility of more efficient exerciseof the muscles around the hip joint, which muscles are weakened by, forinstance, surgery, in which a hip prosthesis has been placed.

An example of a hip orthosis according to the invention will now beexplained in more detail with reference to the drawings, in which:

FIG. 1 shows a perspective front view of a first exemplary embodimentduring use, when the wearer is standing;

FIG. 2 shows a similar view to FIG. 1 when the wearer is sitting;

FIG. 3 shows a top plan view of the exemplary embodiment shown in FIG.2;

FIG. 4 a shows a detail of the first exemplary embodiment in theposition shown in FIG. 1;

FIG. 4 b shows a detail of the first exemplary embodiment in theposition shown in FIG. 2;

FIG. 5 a shows a similar detail to FIG. 4 a of a second exemplaryembodiment;

FIG. 5 b shows a similar detail to FIG. 4 b of a second exemplaryembodiment:

FIG. 6 a shows a similar view to FIG. 1 of the first exemplary isembodiment in untensioned condition;

FIG. 6 b shows the orthosis of FIG. 6 a in tensioned in condition;

FIG. 7 a shows a similar view to FIG. 1 of a third exemplary embodimentin untensioned condition; and

FIG. 7 b shows the orthosis of FIG. 7 a in tensioned condition.

FIG. 1 shows an embodiment of a hip orthosis 2 for preventing thedislocation of a hip according to the invention. In FIG. 1, the hiporthosis 2 has been fitted to a person in standing position. Theorthosis 2 is provided with an upper leg engaging part 4, which isarranged for engaging an upper leg of the person, in use, and a trunkengaging part 6, which is arranged for engaging the trunk of the person,in use. The trunk engaging part 6 is provided with a trunk girding part34 which girds the trunk during use. The upper leg engaging part 4 andthe trunk engaging part 6 are intercoupled by means of coupling means 8,10. The coupling means comprise a connecting part 8 connected with theupper leg engaging part 4 and a coupling part 10 connected with thetrunk engaging part 6, which parts 8, 10 are rotatable with respect toeach other during use. In the Figure, reference numeral 25 designates avirtual point of rotation, about which point of rotation the trunkengaging part 6 and upper leg engaging part 4 are rotatable with respectto each other. Here, the orthosis 2, in particular the trunk engagingpart 6, is designed such that the virtual point of rotation 25 is, inuse, substantially on a virtual line 24 which intersects the two hipballs of the wearer of the orthosis. The connecting part 8 reachesbeyond the point of rotation 25, viewed in a direction from the upperleg engaging part 4 towards the point of rotation 25. The coupling part10 engages the portion of the connecting part 8 reaching beyond thepoint of rotation 25. The connecting part 8 and the coupling part 10engage with respect to each other in a point of contact 12.

In FIG. 1, the connecting part 8 is provided with a resilient element14. In the embodiment shown, the resilient element 14 comprises a leafspring from, for instance, metal or plastic. Due to the resilientelement 14, the orthosis is capable of, operatively, exerting a forceand/or a moment on the upper leg which makes the upper leg abduct,viewed from the front side of the person, preferably independently ofthe position of the upper leg with respect to the trunk. In addition,the person has more freedom of movement, since the upper leg canpreferably move in all directions. This offers more comfort and thepossibility of more efficient exercise of the muscles around the hipjoint, which muscles are weakened by, for instance, surgery.

In use, the resilient element 14 exerts a force on the upper legengaging part 4 and the trunk engaging part 6, so that the connectingpart 8 and the coupling part 10 are pretensioned with respect to eachother, see FIG. 1 and FIG. 6 b. The force is directed such that, in use,the resilient element 14 exerts a force F₁ directed outwards on theupper leg via a lower pressure plate 16 of the upper leg engaging part4, and a force F₂ directed inwards on the upper leg via an upperpressure plate 18 of the upper leg engaging part 4. It will be clearthat, in this example, the force F₁ is thus directed transversely to thesagittal plane, in the lateral direction, and the force F₂ is thusdirected transversely to the sagittal plane, in the medial direction. Itwill be clear that the resilient element 14 thus exerts moment on theupper leg engaging part 4 and consequently, in use, on the upper leg.

The moment exerted on the upper leg may, for instance, press the hipinto its socket. In FIG. 1, the coupling part 10 is provided with asleeve 20 which prevents an outward movement of an end 22 of theconnecting part 8. Here, the end 22 of the connecting part 8 is slidablypositioned in the sleeve 20 of the coupling part 10. Consequently, theresilient element 14 exerts a force F₁ directed outwards on the couplingpart 10 via the end 22 in the point of contact 12. It will be clearthat, in this example, the force F₁ is thus directed transversely to thesagittal plane, in the lateral direction, for instance along the virtualline 24. The sleeve 20 can be designed as a rigid element from, forinstance, metal or plastic, but also as a flexible, elastic or resilientpart from, for instance, rubber or (plastic) cloth.

In FIG. 1, the wearer of the orthosis is in a standing position. Thepoint of contact 12 is then substantially at some distance above thepoint of rotation 25, and therefore above the line 24, see FIG. 4 a. Thelower and upper pressure plate 16 and 18, respectively, aresubstantially below the line 24. As a result, the resilient element 14will effectively exert a force F and a moment M on the hip joint of theupper leg, which joint is located on line 24, while the force F isdirected substantially inwards in the embodiment shown in FIG. 1. Itwill be clear that, in this example, the force F is thus directedtransversely to the sagittal plane, in a medial direction, for instancealong the virtual line 24. As a result, the hip is pressed into itssocket, so that the risk of dislocation is reduced further. In theembodiment shown in FIG. 1, the moment M is directed such that the kneeof the upper leg is pressed substantially outwards, in a directiontransverse to the sagittal plane. As a result, too great an adduction ofthe upper leg (towards the other leg), which increases the risk ofdislocation of the hip, can be prevented.

FIG. 2 shows the first exemplary embodiment with a person in a sittingposition. FIG. 2 again shows the line 24 through the hip balls of theperson. The hip orthosis 2 is designed such that the point of contact 12can move with respect to the trunk engaging part 6 if the upper leg ismoved relative to the trunk, see FIGS. 4 a and 4 b. In FIG. 2 and FIG. 4b, the point of contact 12 is substantially at some distance beyond thepoint of rotation 25, and therefore beyond the line 24, viewed from thefront side of the person. The lower and upper pressure plate 16 and 18,respectively, are substantially in front of the line 24. Also in thissitting position, the resilient element 14 will effectively exert aforce F and a moment M on the hip joint of the upper leg, which joint islocated on the line 24, while the force F is substantially directedinwards. It will be clear that, in this example, the force F is thusdirected transversely to the sagittal plane, in the medial direction.Thus, the hip is pressed into its socket, so that the risk ofdislocation is reduced. In FIG. 2, the resilient element 14 will alsoexert the moment on the upper leg engaging part 4 and consequently, inuse, on the upper leg. In the sitting condition shown in FIG. 2 and FIG.4 b, the point of contact 12 is located in different position withrespect to the trunk from the position in the standing condition shownin FIG. 1 and FIG. 4 a. In both cases, the point of contact 12 islocated substantially at some distance beyond a point of rotation 25,located on the line 24 through the two hip balls of the person, viewedin a direction from the upper leg engaging part 4 towards the point ofrotation 25. As a result, in both FIG. 1 and FIG. 2, the moment M isdirected such that the knee of the upper leg is pressed substantiallyoutwards, in a direction transverse to the sagittal plane.

FIG. 3 shows a top plan view of an embodiment of the orthosis 2according to FIG. 1, with a sitting person. Therein, it is indicatedthat the force of the resilient element 14 preferably substantiallyengages the coupling part 10 in the point of contact 12, while the pointof contact 12, viewed from the front side of the person, is locatedbeyond the line 24 through the hip balls of the person. The resultingforce F₃ exerted by the upper leg engaging part 4 on the coupling part10, and therefore on the trunk engaging part 6, will therefore belocated on the rear side of the person. By the trunk girding part 34,this force F₃ is guided from the trunk engaging part 6 along the trunkto the pressure area, which pressure area is located on the side 36 ofthe trunk facing away from the coupling part 10. The force F₄ resultingfrom force F₃ is also located on this side 36 of the person facing awayfrom the coupling part 10. As a result, forces which act on the trunkengaging part can be supported on the trunk without the trunk engagingpart having the tendency to twist.

The trunk girding part 34 may, for instance, be designed such that thetrunk girding part 34 can substantially only absorb tensile forces inthe circumferential direction of the trunk girding part 34, and cannotabsorb forces ion a direction transverse to the trunk girding part 34.Preferably, at least a part of the trunk girding part 34 is integrallyprovided with a flexible and/or resilient material. Such material may,for instance, wholly or partly gird the respective part of the trunk. Ifthe trunk girding part 34 has an at least partly resilient design, thetrunk girding part 34 may also, for instance, contribute to a clampingforce which keeps the trunk engaging part 6 positioned with respect tothe trunk. If the trunk girding part 34 is provided with a flexible orresilient portion, the trunk girding part 34 forms a girding arc Baround the trunk side 36 facing away from the coupling part, whichgirding arc makes it possible to absorb the resulting force F₄ on therear side of the trunk.

FIG. 4 a shows a side elevational view of a portion of the connectingpart 8 and the coupling part 10 of the embodiment of the orthosis 2 fromFIG. 1. Here, the parts are shown in the positions which they assumewith respect to one another if the orthosis 2 has been fitted to astanding person. The hip orthosis 2 is arranged such that the connectingpart 8 reaches beyond the point of rotation 25, viewed in the directionfrom the upper leg engaging part 4 towards the point of rotation 25. Theend 22 having a rod-shaped design of the connecting part 8 is located inthe sleeve 20 of the coupling part 10, which engages the end 22 of theconnecting part 8 reaching beyond the point of rotation 25, andoperatively prevents a movement of the rod-shaped end 22 in a directiondirected away from the person (at least outwards, transverse to thesagittal plane). Then, the point of contact 12 is in a first position Q,in the top of the sleeve 20, viewed from the person, substantially abovethe point of rotation 25. When the person sits down, the situation isobtained as shown in FIG. 4 b. Here, the point of contact 12 has shiftedfrom the first position Q through a path 26 to a second position R,which is substantially located in the rear of the sleeve 20,substantially beyond the point of rotation 25 viewed from the front sideof the person. In each position Q, R, the point of contact 12 is locatedat a distance from the point of rotation 25, and consequently the line24, viewed in a direction from the upper leg engaging part 4 towards thepoint of rotation 25. Thus, in a simple and inexpensive manner, a forceand a moment can be applied to the hip joint.

FIG. 5 a shows a side elevational view of a portion of the connectingpart 8 and the coupling part 10 of a second embodiment of the orthosis2. Here, the parts are shown in the positions which they assume withrespect to one another if the orthosis 2 has been fitted to a standingperson. The connecting part 8 is provided with an annular part 28, whichis coupled to the trunk engaging part 6 by means of coupling loops 30 ofthe coupling part 10. The operation of the exemplary embodiment shown inFIGS. 5 a and 5 b is analogously to the operation of the exemplaryembodiment shown in FIGS. 1-4. Here, the annular part rotates about acenter 32, and a point of contact 12 shifts from the first position Qwhere the point of contact was located in the standing position to asecond position R, see FIGS. 5 a and 5 b.

FIG. 6 a shows the embodiment of the orthosis 2 according to FIG. 1,during fitting. The upper leg engaging part 4 has been fitted to theupper leg. The trunk engaging part 6 has not yet been fitted to thetrunk. In this situation, the resilient element 14, designed as a leafspring, is in untensioned condition and recedes away from the upper leg.FIG. 6 b shows the embodiment of the orthosis 2 according to FIG. 1which has been fitted completely to a standing person. The upper legengaging part 4 has been fitted to the upper leg. The trunk engagingpart 6 has been fitted to the trunk. In this situation, the resilientelement 14 has been pulled through the sleeve 20 of the coupling part 10to the trunk and is therefore in a tensioned condition substantiallyalong the upper leg. The tensioned resilient element 14 exerts the forceF₁ directed outwards on the upper leg via the lower pressure plate 16 ofthe upper leg engaging part 4, and the force F₂ directed inwards on theupper leg via the upper pressure plate 18 of the upper leg engaging part4. The sleeve 20 prevents a movement directed outwards of the end 22 ofthe connecting part 8. The resilient element 14 consequently exerts theforce F₃ directed outwards on the coupling part 10 via the end 22. Inthis manner, the orthosis 2 offers a great wearing comfort, while hipdislocation is prevented well.

FIGS. 7 a and 7 b show a third embodiment of the orthosis 2. In thisexample, the connecting part 8 is provided with a resilient element 14,comprising a leaf spring in the embodiment shown. In this example, thecoupling part 10 is provided with the sleeve 20 which, operatively,prevents a movement directed outwards of the end 22 of the connectingpart 8.

In FIGS. 7 a and 7 b, the upper leg engaging part 4 comprises a band 40enclosing the upper leg. In this example, the upper leg engaging part 4further comprises a lever 38. The lever 38 is hingedly connected orhingedly connectable with the band 40 in a first hinge point 44. In thisexample, the leaf spring is hingedly connected or hingedly connectablewith the lever 38 in a second hinge point 46. In this example, the leverhas a substantially rigid design and is, for instance, manufactured fromplastic or metal.

The embodiment of the orthosis 2 shown in FIGS. 7 a and 7 b can befitted to the user as follows.

FIG. 7 a shows the third embodiment of the orthosis 2, during fitting.The upper leg engaging part 4 has been fitted to the upper leg. To thisend, in this example, the band 40 has been fitted around the upper leg,for instance by closing a snap connection or buckle of the band. Thetrunk engaging part 6 has also already been fitted to the trunk. The end22 of the connecting part 8, in this example the end of the leaf spring,can then be inserted into the sleeve.

It is also possible that the trunk engaging part 6 and upper legengaging part 4 are, for instance, inseparably connected. To this end,for instance the connecting part 8 and the coupling part 10 can beconnected, optionally inseparably, for instance by means of a snapconnection. Here, the connecting part 8 and the coupling part 10 may,for instance, be connected such that the user cannot detach or is notallowed to detach the connection. In that case, the user will not insertthe end 22 of the connecting part 8 into the sleeve 20, since theconnecting part 8 has then already been connected with the coupling part10. Here, it is possible that, for instance, an expert, such as amedical instrument maker, or another person who takes the user'smeasurements for the orthosis can and/or is allowed to detached theconnection between the trunk engaging part 6 and upper leg engaging part4. To this end, the connecting part 8 may, for instance, be connectedwith the coupling part 10 such that the connection is only detachable byutilizing a special tool or a key.

Since, in this example, the resilient element 14 is connected to theband 40 fitted to the upper leg via the second hinge point 46, the lever38 and the first hinge point 44, inserting the end 22 into the sleeve 20requires little force and/or effort, In this situation, the resilientelement 14, designed as a leaf spring, is in an untensioned conditionand recedes away from the upper leg. To this end, in an untensionedcondition, the leaf spring may, for instance, trace an arc or comprise abend. In this situation, the lever 38 is not excited and, in thisexample, recedes away from the upper leg and from the resilient element14.

Then, the lever 38 can be tilted about the first hinge point 44, so thatthe lever 38 is moved towards the upper leg. Here, the second hingepoint 46 will be moved towards the upper leg, and the leaf spring willbe tensioned. The resilient element 14 is thus in the tensionedcondition substantially along the upper leg, see FIG. 7 b. As soon asthe resilient element 14 has been tensioned, the lever 38 and theresilient element can be fixed with respect to each other, so that thetensioned condition of the resilient element 14 is maintained. In thisexample, to this end, the lever 38 is provided with fixing means 48, forinstance a snap connection, which engage the resilient element 14.Preferably, the lever 38 and the resilient element 14 are fixed withrespect to each other such that the fixation cannot be broken byaccident, at least is difficult to break by accident. To this end, thesnap connection may, for instance, be provided with an operating elementwhich is to be operated with at least two fingers.

It will be clear that, by using the lever 38 for tensioning theresilient element 14, it is simpler to fitting the orthosis 2 to theuser, since less force needs to be exerted for tensioning the resilientelement 14.

As can seen in FIG. 7 b, the tensioned resilient element 14 exerts theforce F₁ directed outwards on the upper leg via the band 40 of the upperleg engaging part 4, and the force F₂ directed inwards on the upper legvia a pressure piece 42 of the upper leg engaging part 4 connected withthe resilient element 14 in this example. The sleeve 20 prevents amovement directed outwards of the end 22 of the connecting part 8. Theresilient element 14 thus exerts the force F₂ directed outwards on thecoupling part 10 via the end 22.

In FIGS. 7 a and 7 b, the resilient element 14 is hingedly connected orhingedly connectable with the lever 38 in the second hinge point 46. Itwill be clear that it is also possible that the connecting part 8 isprovided with a, for instance, at least partly substantially rigidsub-connecting part which is hingedly connected or hingedly connectablewith the lever 38 in the second hinge point 46, while the sub-connectingpart further comprises the resilient element 14. The sub-connecting partmay, for instance, comprise a substantially rigid rod or strip whichcomprises a leaf spring near the end directed towards the coupling part10.

The invention is by no means limited to the embodiments shown in theFigures. Various modifications are possible within the framework of theinvention as set forth in the following claims.

Thus, it is, for instance, possible that the coupling part is providedwith at least one resilient element. Also, the connecting part may beprovided with more than one resilient element.

In one alternative embodiment, the connecting part is designed as asubstantially rigid element which is hingedly connected with the upperleg engaging part. Here, if only the upper leg engaging part has beenfitted to a person, the connecting part can recede away from the upperleg under the influence of a spring force provided by a, resilientelement, for instance a coil spring or a piece of elastomer. The trunkengaging part can then be designed in accordance with the embodimentshown in FIG. 1.

In another alternative embodiment, the upper leg engaging part iscompletely designed as a rigid part. In this case, the coupling partmay, for instance, be designed as a sleeve or shell which is connectedwith the trunk engaging part by means of a resilient element in order toexert a force and/or moment on the hip joint via the upper leg engagingpart in use.

In a further alternative embodiment, both the connecting part and thecoupling part comprise a rigid bracket between which a resilientelement, for instance a draw spring or compression spring, elastic,etc., is tensioned. Here, the resilient element is positioned such thatthe element exerts a force on the connecting part and the coupling partalong a line of force, which line of force is operatively substantiallylocated at some distance from the line through the two hip balls of theperson, and which line of force, in neutral position, runs substantiallyparallel to the line through the two hip balls. If the upper leg ismoved relative to the trunk, the direction of the line of force willalso vary with respect to the line through the two hip balls.

Further, the upper leg engaging part may be connected with the trunkconnecting part via at least two, preferably three, hinges, whose axesof rotation run substantially parallel to the line through the two hipballs. Thus, the upper leg engaging part can hinge and translate withrespect to the trunk engaging part so that the risk of twisting of thetrunk engaging part around the trunk is reduced, while the freedom ofmovement of the upper leg remains is limited to the substantiallyforward and backward directions. Here, for instance, the upper legengaging part may be connected with the connecting part via resilientelement, in order to apply a force and/or moment to the hip joint.

The at least one resilient element mentioned may be designed indifferent manners and comprise, for instance, a leaf spring, torsionspring, draw spring, compression spring, gas spring, elastic materialand/or the like.

Such variants are all understood to fall within the framework of theinvention.

1. A hip orthosis, comprising: a trunk engaging part; an upper legengaging part; a coupling device intercoupling the trunk engaging partto the tipper leg engaging part, the coupling device having at least oneresilient element for operatively preventing an adducting movement of antipper leg engaged by the upper leg engaging part by a spring force, thecoupling device comprising a connecting part connected to the upper legengaging part and a coupling part connected to the trunk engaging part,wherein, during use, the connecting part is rotatable about a point ofrotation with respect to the coupling part, wherein the point ofrotation is defined as a virtual point of rotation; wherein theresilient element is defined as a leaf spring; wherein the at least oneresilient element exerts a pressing force on a hip joint, such that ahip is pressed into a socket thereof under the influence of the pressingforce.
 2. The hip orthosis according to claim 1, wherein the force isdirected substantially inwards toward the wearer.
 3. The hip orthosisaccording to claim 1, wherein the at least one resilient element exertsa moment on the hip joint.
 4. The hip orthosis according to claim 1,wherein the at least one resilient element exerts a moment on the hipjoint.
 5. The hip orthosis according to claim 4, wherein the moment isdirected such that the upper leg is rotated substantially outwards, in adirection transverse to the sagittal plane.
 6. The hip orthosisaccording to claim 1, wherein the trunk engaging part is arranged suchthat a point of rotation is located on a line which generally intersectstwo hip balls of a wearer of the orthosis.
 7. The hip orthosis accordingto claim 1, wherein the connecting part and the coupling part arepretensioned with respect to each other.
 8. The hip orthosis accordingto claim 7, the resilient element exerts a force directed outwards onthe coupling part.
 9. The hip orthosis according to claim 1, whereinwhen the upper leg engaging part is fitted to the upper leg, the leafspring is arranged to move away from the upper leg in an untensionedcondition, and is located substantially along the upper leg in atensioned condition.
 10. The hip orthosis according to claim 1, whereinthe hip orthosis includes a lever arranged to move the at least oneresilient element into a tensioned condition.
 11. The hip orthosisaccording to claim 10, wherein the hip orthosis is provided with afixing device arranged to fix the lever and the at least one resilientelement with respect to each other to maintain the at least oneresilient element in the tensioned condition.
 12. The hip orthosisaccording to claim 1, wherein the connecting part and the coupling partengage each other at least in a point of contact, which point of contactis arranged to operatively move with respect to the trunk engaging partif the upper leg is moved relative to a trunk.
 13. The hip orthosisaccording to claim 12, wherein the point of contact is located at adistance from the point of rotation.
 14. The hip orthosis according toclaim 13, wherein both in standing and in sitting condition, the pointof contact is located beyond the point of rotation, viewed in adirection from the upper leg engaging part towards the point ofrotation.
 15. The hip orthosis according to claim 1, wherein theconnecting part reaches beyond the point of rotation viewed in adirection from the upper leg engaging part towards the point ofrotation.
 16. The hip orthosis according to claim 15, wherein both in astanding and in a sitting condition, the connecting part reaches beyondthe point of rotation, viewed in a direction from the upper leg engagingpart towards the point of rotation.
 17. The hip orthosis according toclaim 15, wherein the coupling part engages at least the portion of theconnecting part reaching beyond the point of rotation, with differentrotational positions of the connecting part.
 18. The hip orthosisaccording to claim 1, wherein the connecting part is slidably coupled tothe coupling part.
 19. The hip orthosis according to claim 14, whereinthe connecting part comprises a rod-shaped end, wherein the couplingpart is arranged for operatively preventing an outward movement of therod-shaped end with respect to the trunk engaging part.
 20. The hiporthosis according to claim 19, wherein the coupling part is providedwith a sleeve for, operatively, at least partly receiving the rod-shapedend therein.
 21. The hip orthosis according to claim 15, wherein theconnecting part comprises an annular part, wherein the coupling part isarranged for operatively preventing an outward movement of the annularpart with respect to the trunk engaging part.
 22. The hip orthosisaccording to claim 1, wherein the trunk engaging part is provided with atrunk girding part arranged for girding a part of a trunk of a wearerwherein the trunk girding part is arranged for guiding a force (F₃)coming from the coupling device to a trunk side facing away from thecoupling device.
 23. The hip orthosis according to claim 22, wherein thetrunk girding part is arranged for substantially only absorbing tensileforces in the circumferential direction of the trunk girding part. 24.The hip orthosis according to claim 23, wherein the girding partincludes a flexible or resilient material.
 25. A method for preventingthe dislocation of a hip of a person, comprising the steps of attachinga trunk engaging part to the trunk of a wearer; attaching an tipper legengaging part to the upper leg of a wearer; intercoupling the trunkengaging part with the upper leg engaging part by connecting aconnecting part with the upper leg engaging part and connecting acoupling part with the trunk engaging part; operatively preventing anadducting movement of an upper leg engaged by the upper leg engagingpart with a spring force provided by at least one resilient elementhaving a leaf spring; responsive to movement of the person, rotating theconnecting part about a point of rotation with respect to the couplingpart, wherein said point of rotation is a virtual point of rotation; andpreventing an inward movement of the associated tipper leg by a springforce; wherein the force is directed substantially such that the hip ispressed into its socket under the influence of that force.
 26. Themethod according to claim 25, wherein the force is directedsubstantially inwards.
 27. The method according to claim 25, wherein theupper leg is rotated substantially outwards, in a direction transverseto the sagittal plane, by a moment.